Serving Cell Interruption in Multicarrier with Shortened Tti Patterns

1. A method in a wireless device for a wireless communication system supporting at least one transmission time interval, TTI, the method comprising: communicating with a network node in a first cell on a first carrier; determining an operation to be performed by the wireless device in a second cell on a second carrier; and performing the determined operation in the second cell while interrupting the communication with the network node in the first cell on the first carrier according to a value of an interruption parameter that does not exceed an interruption threshold that depends on a duration of a TTI on the first carrier and further depends on a frequency separation between the first carrier and the second carrier.

2. The method of claim 1 , wherein the interruption parameter is at least one of: a time period over which the interruption occurs, a packet loss rate and a number of uplink feedback signals in response to receiving downlink data in the first cell.

3. The method of claim 2 , wherein the packet loss rate is expressed as a probability of missed acknowledgement/non-acknowledgement, ACK/NACK, signals in the uplink by the wireless device in response to receiving downlink data in the first cell.

4. The method of claim 1 , wherein the operation requires the wireless device to reconfigure a bandwidth of at least one of the first cell and the second cell.

5. The method of claim 1 , wherein the operation includes at least one of: a reconfiguration of at least one of the first cell and the second cell, measurements on a cell which is deactivated, a carrier frequency change, setting up a new cell and a release of a cell.

6. The method of claim 1 , wherein the interruption threshold depends on whether the first carrier is in a licensed band and the second carrier is in an unlicensed band.

7. A wireless device for a wireless communication system supporting at least one transmission time interval, TTI, the wireless device comprising: processing circuitry configured to: communicate with a network node in a first cell on a first carrier; determine an operation to be performed by the wireless device in a second cell on a second carrier; perform the determined operation in the second cell; and interrupt the communicating with the network node in the first cell on the first carrier according to a value of an interruption parameter that does not exceed an interruption threshold that depends on a duration of a TTI on the first carrier and further depends on a frequency separation between the first carrier and the second carrier.

8. A method in a network node for a wireless communication system supporting at least one transmission time interval, TTI, the method comprising: communicating with a wireless device in a first cell on a first carrier; configuring the wireless device to perform an operation in a second cell on a second carrier; determining a value of an interruption parameter according to which communication with the wireless device in the first cell on the first carrier is to be interrupted, the value of the interruption parameter not exceeding an interruption threshold that is based on a duration of a TTI on the first carrier and further depends on a frequency separation between the first carrier and the second carrier; and interrupting communication with the wireless device in the first cell on the first carrier according to the value of the interruption parameter while the wireless device performs the operation.

9. The method of claim 8 , wherein the interruption parameter at least one of: a time period over which the interruption occurs, a packet loss rate and a number of uplink feedback signals transmitted by the wireless device in response to receiving downlink data in the first cell.

10. The method of claim 9 , wherein the packet loss rate is expressed as a probability of missed acknowledgement/non-acknowledgement, ACK/NACK, signal in the uplink by the wireless device in response to receiving downlink data in the first cell.

11. The method of claim 8 , wherein the operation requires the wireless device to reconfigure a bandwidth of at least one of the first cell and the second cell.

12. The method of claim 8 , wherein the operation includes at least one of: a reconfiguration of at least one of the first cell and the second cell, measurements on a cell which is deactivated, a carrier frequency change, setting up a new cell and a release of a cell.

13. The method of claim 8 , wherein the threshold interruption depends on whether the first carrier is in a licensed band and the second carrier is in an unlicensed band.

14. A network node for a wireless communication system supporting at least one transmission time interval, TTIs, the network node comprising: a transceiver configured to communicate with a wireless device in a first cell on a first carrier; and processing circuitry configured to: configure the wireless device to perform an operation in a second cell on a second carrier; determine a value of an interruption parameter according to which communication with the wireless device in the first cell on the first carrier is to be interrupted, the value of the interruption parameter not exceeding an interruption threshold that is based on a duration of a TTI on the first carrier and further depends on a frequency separation between the first carrier and the second carrier; and interrupt communication with the wireless device in the first cell on the first carrier according to the value of the interruption parameter while the wireless device performs the operation.